The need for fire-resistant materials is ever increasing. Industry's demands for such materials grow not only because of the increasing number of outlets for products that are exposed in their use to possibilities of fire but because the processes in their production frequently require more exposure to heat. Similarly, such exposure very often includes contacts with corrosive substances such as alkalies, acids and solvents. Solutions to such problems have been sought by the introduction into plastics of inorganic salts or metallic soaps or bromine containing compounds as can be seen in such recent patents as U.S. Pat. Nos. 3,819,577; 3,821,141; and 3,826,777. Hithertofore, no one, despite the wide use in industry of combinations of inorganic fillers and organic polymers, has supplied a combination that has the unique combination of an exceptionally low flame spread index with good strengths and chemical and other resistances.
An object of this invention is to provide such chemical compositions. An additional aim of this invention is the provision of inorganic mixtures which may be readily incorporated into organic polymeric substances which then may be shaped into articles which have, by virtue of said mixtures, great resistivity to combustion, heat, solvents, and corrosive substances. These and other purposes will appear hereinafter.